In current pure electric vehicles, a single electric motor, in combination with a transmission power system having one or two gears or other numbers of gears, is generally used for vehicle driving. The dynamic performance of a pure electric vehicle is directly limited by the peak torque and power characteristic of the single electric motor. The one gear transmission system has only one speed ratio, and thus cannot provide a large room for economic optimization; on the other hand, it is possible to optimize the dynamic performance and economics of the two-gear transmission system, but power interruption may occur which affects the driving comfort.
In addition, pure electric vehicles driven by dual motors now get more and more attention for the reasons that higher power output and more flexible control strategy can be provided and gear switching without power interruption can be achieved, and economic optimization techniques for the pure electric vehicles have been proposed. In these techniques, the gears of the motors are only selected based on the vehicle speed and the pressed degree of the acceleration pedal, and the torque distribution of the two motors is determined based on the selected gears of the motors, so it is not easy to obtain optimized economics.